Merge pull request #2881 from zhang2014/feature/support_optimize_predicate_for_view

ISSUES-863 support optimize predicate for view

dbms/src/Storages/StorageView.cpp

@@ -1,11 +1,14 @@
+#include <Interpreters/InterpreterSelectQuery.h>
 #include <Interpreters/InterpreterSelectWithUnionQuery.h>
 #include <Parsers/ASTCreateQuery.h>
+#include <Parsers/ASTSubquery.h>
 
 #include <Storages/StorageView.h>
 #include <Storages/StorageFactory.h>
 
 #include <DataStreams/MaterializingBlockInputStream.h>
 
+#include <Common/typeid_cast.h>
 
 namespace DB
 {
@@ -13,6 +16,7 @@ namespace DB
 namespace ErrorCodes
 {
     extern const int INCORRECT_QUERY;
+    extern const int LOGICAL_ERROR;
 }
 
 
@@ -31,14 +35,26 @@ StorageView::StorageView(
 
 BlockInputStreams StorageView::read(
     const Names & column_names,
-    const SelectQueryInfo & /*query_info*/,
+    const SelectQueryInfo & query_info,
     const Context & context,
     QueryProcessingStage::Enum processed_stage,
     const size_t /*max_block_size*/,
     const unsigned /*num_streams*/)
 {
     checkQueryProcessingStage(processed_stage, context);
-    BlockInputStreams res = InterpreterSelectWithUnionQuery(inner_query, context, column_names).executeWithMultipleStreams();
+
+    BlockInputStreams res;
+
+    if (context.getSettings().enable_optimize_predicate_expression)
+    {
+        replaceTableNameWithSubquery(typeid_cast<ASTSelectQuery *>(query_info.query.get()), inner_query);
+        auto res_io = InterpreterSelectQuery(query_info.query, context, column_names, processed_stage).execute();
+
+        res.emplace_back(res_io.in);
+        return res;
+    }
+
+    res = InterpreterSelectWithUnionQuery(inner_query, context, column_names).executeWithMultipleStreams();
 
     /// It's expected that the columns read from storage are not constant.
     /// Because method 'getSampleBlockForColumns' is used to obtain a structure of result in InterpreterSelectQuery.
@@ -48,6 +64,23 @@ BlockInputStreams StorageView::read(
     return res;
 }
 
+void StorageView::replaceTableNameWithSubquery(ASTSelectQuery * select_query, ASTPtr & subquery)
+{
+    ASTTablesInSelectQueryElement * select_element = static_cast<ASTTablesInSelectQueryElement *>(select_query->tables->children[0].get());
+
+    if (!select_element->table_expression)
+        throw Exception("Logical error: incorrect table expression", ErrorCodes::LOGICAL_ERROR);
+
+    ASTTableExpression * table_expression = static_cast<ASTTableExpression *>(select_element->table_expression.get());
+
+    if (!table_expression->database_and_table_name)
+        throw Exception("Logical error: incorrect table expression", ErrorCodes::LOGICAL_ERROR);
+
+    table_expression->database_and_table_name = {};
+    table_expression->subquery = std::make_shared<ASTSubquery>();
+    table_expression->subquery->children.push_back(subquery->clone());
+}
+
 
 void registerStorageView(StorageFactory & factory)
 {

dbms/src/Storages/StorageView.h

@@ -2,6 +2,7 @@
 
 #include <ext/shared_ptr_helper.h>
 #include <Storages/IStorage.h>
+#include <Parsers/ASTSelectQuery.h>
 
 
 namespace DB
@@ -38,6 +39,8 @@ private:
     String table_name;
     ASTPtr inner_query;
 
+    void replaceTableNameWithSubquery(ASTSelectQuery * select_query, ASTPtr & subquery);
+
 protected:
     StorageView(
         const String & table_name_,

dbms/tests/queries/0_stateless/00597_push_down_predicate.reference

@@ -20,5 +20,6 @@
 2000-01-01	1	test string 1	1	2000-01-01	1	test string 1	1
 2000-01-01	1	test string 1	1
 1	2000-01-01	2000-01-01	1	test string 1	1
+2000-01-01	1	test string 1	1
 -------Push to having expression, need check.-------
 -------Compatibility test-------

dbms/tests/queries/0_stateless/00597_push_down_predicate.sql

@@ -1,8 +1,10 @@
 SET send_logs_level = 'none';
 
 DROP TABLE IF EXISTS test.test;
+DROP TABLE IF EXISTS test.test_view;
 
 CREATE TABLE test.test(date Date, id Int8, name String, value Int64) ENGINE = MergeTree(date, (id, date), 8192);
+CREATE VIEW test.test_view AS SELECT * FROM test.test;
 
 INSERT INTO test.test VALUES('2000-01-01', 1, 'test string 1', 1);
 INSERT INTO test.test VALUES('2000-01-01', 2, 'test string 2', 2);
@@ -50,6 +52,9 @@ SELECT * FROM (SELECT * FROM (SELECT * FROM test.test) ANY LEFT JOIN (SELECT * F
 -- Optimize predicate expression with join query and qualified
 SELECT * FROM (SELECT 1 AS id, toDate('2000-01-01') AS date FROM system.numbers LIMIT 1) ANY LEFT JOIN (SELECT * FROM test.test) AS b USING date WHERE b.id = 1;
 
+-- Optimize predicate expression with view
+SELECT * FROM test.test_view WHERE id = 1;
+
 SELECT '-------Push to having expression, need check.-------';
 SELECT id FROM (SELECT min(id) AS id FROM test.test) WHERE id = 1; -- { serverError 277 }
 
@@ -57,3 +62,4 @@ SELECT '-------Compatibility test-------';
 SELECT * FROM (SELECT 1 AS id, toDate('2000-01-01') AS date FROM system.numbers LIMIT 1) ANY LEFT JOIN (SELECT * FROM test.test) AS b USING date WHERE b.date = toDate('2000-01-01'); -- {serverError 47}
 
 DROP TABLE IF EXISTS test.test;
+DROP TABLE IF EXISTS test.test_view;